This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The central hypothesis of this project is that the TPCN1 calcium release channel is in part responsible in regulating the key transient increases in intracellular calcium concentration needed for the correct progression of cytokinesis. In addition, it is hypothesized that this regulation is via direct involvement of the regulatory kinases responsible for myosin light chain 2-phosphorylation, activation, and the subsequent cleavage furrow formation necessary for completion of cytokinesis.